The purpose ofthe Training and Career Development Program ofthe Primary Immune Deficiency Treatment Consortium (PIDTC) is to provide career development that will enhance educafion at the clinical postdoctoral level. By training investigators specifically in the area of PID, the cadre of physician-scienfists involved in elucidating the pathogenesis ofthese disorders and developing and applying improved therapies will be augmented. Clinical invesfigators caring for pafients with PID require a complex set of skills, including knowledge of immune reconstitufion and transplant immunology, diagnosis and medical management of pafients with PID, and expertise in hematology, infecfious diseases, genefics and critical care of ill pafients undergoing hematopoietic cell transplantafion (HCT). They also need to familiarize and interactwith PID Pafient Advocacy Groups. The PIDTC brings together specialists from North America and provides a unique platform to train new investigators in the course of disseminating knowledge to providers, patients and families. The goal of PIDTC training grants is to provide support for research at the level ofthe clinical post-doctoral fellow. Our experience with the first four years of awardees reinforces much of what we plan for the next cycle. We have seen the benefits of networking and formal presentations and propose to enhanceihat type of participafion. We have also noted the challenges faced by those who plan an academic career but this is an especially acute issue in the field of PIDs, where the study of rare diseases often requires a network of invesfigators, a difficult proposifion for junior faculty. The Specific Aims of this Program are to (1) select the highest quality candidates for training support in Primary Immune Deficiency research, (2) incorporate the supported Fellows into PIDTC activities to enhance their education and networking opportunities, and (3) continue to track the outcome of training of supported fellows, based on scientific publications and career advancement. The PIDTC provides a network of committed invesfigators with specific expertise in the biology, diagnosis and treatment of PIDs, and will serve as an important training ground for emerging investigators. The structure ofthe PIDTC consortium will facilitate the development of junior invesfigators studying immune deficiencies.